I was surprised how patination is both art and chemistry; controlled oxidation, acids

https://www.scribd.com/document/1039869947/Salvo-Metal-Works-and-the-Truth-of-Copper-Personalized-Chimney-Shrouds-that-Endure-183965

I was surprised how patination is both art and chemistry; managed oxidation, acids, and waxes develop living surfaces that advance with climate yet remain protectively secured.